Manufacturing businesses are sitting on a ticking cybersecurity time bomb. Old systems, open networks, and unchecked access points leave critical operations exposed to costly attacks. Learn exactly where your biggest risks lie—and how to fix them quickly without a full IT overhaul.
Manufacturing today depends on a mix of old and new technologies. While this blend drives productivity, it also creates security weak spots attackers love to exploit. The good news? You don’t need to rebuild everything from scratch to protect your operation. Let’s discuss the top vulnerabilities and practical ways to lock them down.
1. Legacy Systems: The Achilles’ Heel You Can’t Ignore
Many manufacturers rely on legacy systems—those machines and software installed years, sometimes decades ago—that still run essential parts of production. These systems weren’t built with modern cybersecurity threats in mind. Because of that, they often lack the ability to receive security updates or patches, leaving them exposed like an open window in a busy street.
Imagine a factory using a decades-old industrial control system (ICS) to manage a production line. This system controls everything from temperature to conveyor speeds. Now, picture that system connected directly to the company’s main network, with no isolation or updated protections. If an attacker gains access, they could manipulate the ICS to cause a shutdown or damage equipment, leading to costly downtime and repairs.
The tricky part is that replacing legacy systems overnight isn’t practical or affordable for most manufacturers. The good news is you can reduce the risk by isolating these systems from your main business network. This means setting up network segments or firewalls so the legacy ICS can’t be accessed directly from other parts of your IT environment. It’s like putting a locked door between the old and new parts of your factory network.
For example, a mid-sized manufacturer I know implemented simple network segmentation to separate their legacy production systems. They didn’t replace their equipment right away, but by creating this barrier, they made it much harder for attackers to move freely across their network. This step alone cut their risk significantly without expensive downtime.
Another practical move is to patch what you can. Sometimes legacy systems have available updates or firmware fixes, and applying these—even if it means scheduling downtime—helps close obvious holes. If no patches are available, focus on restricting access to only essential personnel and systems.
The takeaway here is to stop thinking of legacy systems as untouchable relics. They are your biggest security blind spot and deserve priority when it comes to limiting exposure. The sooner you create barriers around them and limit who or what can reach them, the more secure your operations become.
2. Exposed PLCs and Industrial Control Systems: Open Doors for Attackers
Programmable Logic Controllers (PLCs) and industrial control systems are the brains behind your manufacturing processes. They regulate machinery, control assembly lines, and keep everything running smoothly. But here’s the catch: many of these critical devices are still accessible from internal networks—or even remotely—without strong security measures in place.
Imagine a scenario where a PLC controlling a bottling line is reachable from the corporate IT network without any restrictions. An attacker who gains entry to the corporate network could then send commands to that PLC, causing the line to stop or produce defective products. This isn’t just a theory—it’s exactly how attacks like Stuxnet operated, targeting industrial environments through poorly secured control devices.
The best way to protect PLCs is to strictly limit who can communicate with them. This means segmenting your ICS network away from your corporate network so even if an attacker breaks into the office systems, they hit a digital firewall before reaching the machines. Use firewalls and access control lists (ACLs) to restrict communication paths and block unnecessary connections.
Monitoring is key, too. Set up tools that watch for unusual activity on your PLC networks—like commands sent at strange hours or from unauthorized devices. This early warning system can catch potential intrusions before they cause damage.
If you don’t have dedicated ICS cybersecurity tools, start with simple steps: create a list of every device that talks to your PLCs, limit that list ruthlessly, and regularly review it.
3. Outdated Firewalls and Network Defenses: Security Theater Isn’t Enough
Many manufacturers rely on firewalls that were configured years ago and never revisited. Or they use basic firewalls that can’t detect modern threats. The result? Open ports and outdated rules that leave your network vulnerable.
Consider a manufacturer who left an old remote desktop port open because it was needed for occasional maintenance. Over time, the port was forgotten but remained accessible. Hackers scanned the network, found the open port, and exploited it to gain entry. That single oversight led to a ransomware attack that shut down operations for days.
To avoid this, firewalls need regular audits. Ask your IT team or service provider to review firewall rules quarterly. Close ports that aren’t in use and restrict inbound traffic to only known, trusted IP addresses.
If your budget allows, upgrade to next-generation firewalls with built-in threat intelligence and intrusion prevention. These firewalls don’t just block traffic—they analyze it for suspicious patterns and stop attacks before they penetrate your defenses.
4. Flat Networks: Why Your Entire Operation Shouldn’t Be One Big Room
A flat network means every device on the network can communicate freely with every other device. It’s like having an open floor plan where anyone can walk into any room. This might have made sense when networks were small and simple, but today, it’s a huge risk.
If one device gets compromised, attackers can move laterally—jumping from your office computers to production systems or vendor portals. This amplifies the damage, turning a small breach into a facility-wide shutdown.
Start by creating network segments for different functions—office computers in one, production machines in another, and guest devices in a separate zone. Even basic VLANs can prevent attackers from freely roaming inside your network.
Segmenting also makes it easier to apply security controls tailored to each group. For example, production devices might need strict monitoring and limited internet access, while office computers require email filtering and endpoint protection.
5. Remote Access Tools Without Proper Controls: Inviting Trouble In
Remote access has become essential for manufacturers managing multiple sites or needing vendor support. But without proper safeguards, these tools become a favorite entry point for cybercriminals.
Imagine an employee accessing the factory network from home using an outdated VPN client without multi-factor authentication. If their password is compromised, attackers can log in as if they were the employee, opening doors wide.
The fix is straightforward. Always require multi-factor authentication (MFA) on remote access tools. Use VPNs with strong encryption, and restrict access to only the users and systems that truly need it. Limit remote connections to specific IP addresses or time windows when possible.
Audit remote access logs regularly to spot unusual login patterns, and revoke access as soon as someone leaves the company or changes roles.
6. Third-Party and Vendor Access: Your Weakest Link?
Vendors and suppliers often need system access for updates or troubleshooting, but their cybersecurity may not match your standards. Attackers increasingly exploit vendor connections to breach manufacturing networks.
Picture a supplier whose compromised laptop connects to your network for routine maintenance. The attacker uses that trusted connection to move inside your systems unnoticed.
To guard against this, enforce strict policies around third-party access. Require vendors to use unique, temporary credentials and limit what they can access. Monitor all vendor activity in real time and revoke access immediately after tasks are completed.
Before granting access, verify that vendors follow strong security practices. If possible, use vendor management platforms that provide controlled, auditable access.
7. Lack of Basic Cyber Hygiene: The Foundation of Defense
Even the best technology fails if people don’t follow basic security practices. Phishing emails, weak passwords, and unpatched software are still the easiest ways attackers break in.
Manufacturing teams are busy and focused on production—not cybersecurity. That’s why simple training, tailored to your environment, is crucial. Teach employees to spot phishing, never share passwords, and report suspicious activity.
Enforce strong password policies—complex, unique, and changed regularly. Automate software updates wherever possible to reduce the risk from known vulnerabilities.
Remember, your people are the first line of defense. Investing a little time in training and policies today pays off by stopping attacks before they start.
3 Clear Actions You Can Take Now
Segment and isolate critical systems so attacks can’t spread across your entire operation.
Control and monitor access rigorously, especially for remote users and vendors.
Make cyber hygiene non-negotiable—train your team and enforce strong password and update policies.
Top 5 FAQs About Manufacturing Cybersecurity Vulnerabilities
1. How do I know if my legacy systems are a risk?
If your equipment or control software hasn’t been updated in years or can’t receive security patches, it’s a red flag. Start by mapping what’s connected and isolating legacy gear from other networks.
2. What’s the easiest way to segment my network?
Using VLANs or physical firewalls to separate office, production, and guest devices is a good start. It doesn’t require ripping out existing infrastructure but greatly limits risk.
3. How often should I review firewall rules?
At least quarterly. Every open port or allowed service is a potential attack vector, so keep your firewall rules tight and updated.
4. Can vendors really cause security breaches?
Yes. Many attacks begin through vendor systems. Limit their access, monitor activity, and require them to follow your security policies.
5. What if I don’t have an IT team?
Start small with network segmentation, strong passwords, and employee training. Consider hiring external cybersecurity consultants to guide you through the process.
Time to Take Control of Your Manufacturing Cybersecurity
You don’t have to overhaul your entire IT environment overnight to protect your business. Start with the biggest vulnerabilities—legacy systems, exposed industrial devices, and open access points—and put practical controls in place. Every step you take today makes your operation safer and more resilient against costly cyberattacks. If you want, I can help you map out a simple, prioritized plan that fits your budget and timeline. Let’s make sure your manufacturing business stays secure and productive—starting now.